Solid fuel burners are disclosed in the following publications:
Publication GB 2101737 discloses a grate to be placed in a furnace, said grate comprising low side walls. The grate can be moved in the furnace in such a manner that for example the cleaning of the furnace is facilitated.
Publication U.S. Pat. No. 2,949,209 discloses a waste burner whose walls contain holes for air intake.
Publication U.S. Pat. No. 3,213,846 discloses a furnace that can be used both for heating and cooking.
Publication U.S. Pat. No. 4,719,899 discloses an arrangement for efficient burning of granular fuel.
Publications U.S. Pat. No. 5,941,234 and WO 98/29686 disclose a burner equipped with holes for air intake, the bottom of which burner is advantageously in an oblique position. The burner can be used in furnaces, such as ovens and fireplaces.
Publication U.S. Pat. No. 5,983,885 discloses a furnace in which pellets can be constantly supplied.
Solid fuel burners can be separate burners placed inside a furnace, burners used without a surrounding furnace, or the burner can be furnace with a mantle that stores thermal energy. Known furnaces comprising a heat storing mantle are typically fireplaces or ovens or combinations of these. The mantle can be for example made of tiles or steatite.
In known burners of solid fuel the fuel charge is usually lit from outside and the combustion is directed from outside the fuel charge to the inside. The fire propagates towards the centre of the fuel charge from all sides, wherein combustion takes place slowly and in an uncontrolled and imperfect manner. The combustion causes a great deal of smoke and the burning temperature is low, wherein large amounts of unburned gases are produced. Substantial production of smoke causes stains the air conduits and the efficiency of the combustion is poor.